JAK/STAT3 and NF-κB Signaling Pathways Regulate Cancer Stem-Cell Properties in Anaplastic Thyroid Cancer Cells

Cancer stem cells: advances in knowledge and implications for cancer therapy

Cancer stem cells (CSCs), a small subset of cells in tumors that are characterized by self-renewal and continuous proliferation, lead to tumorigenesis, metastasis, and maintain tumor heterogeneity. Cancer continues to be a significant global disease burden. In the past, surgery, radiotherapy, and chemotherapy were the main cancer treatments. The technology of cancer treatments continues to develop and advance, and the emergence of targeted therapy, and immunotherapy provides more options for patients to a certain extent. However, the limitations of efficacy and treatment resistance are still inevitable. Our review begins with a brief introduction of the historical discoveries, original hypotheses, and pathways that regulate CSCs, such as WNT/β-Catenin, hedgehog, Notch, NF-κB, JAK/STAT, TGF-β, PI3K/AKT, PPAR pathway, and their crosstalk. We focus on the role of CSCs in various therapeutic outcomes and resistance, including how the treatments affect the content of CSCs and the alteration of related molecules, CSCs-mediated therapeutic resistance, and the clinical value of targeting CSCs in patients with refractory, progressed or advanced tumors. In summary, CSCs affect therapeutic efficacy, and the treatment method of targeting CSCs is still difficult to determine. Clarifying regulatory mechanisms and targeting biomarkers of CSCs is currently the mainstream idea.

Targeted immunotherapy to cancer stem cells: A novel strategy of anticancer immunotherapy

Cancer is a major disease that endangers human health. Cancer drug resistance and relapse are the two main causes contributing to cancer treatment failure. Cancer stem cells (CSCs) are a small fraction of tumor cells that are responsible for tumorigenesis, metastasis, relapse, and resistance to conventional anticancer therapies. Therefore, CSCs are considered to be the root of cancer recurrence, metastasis, and drug resistance. Novel anticancer strategies need to face this new challenge and explore their efficacy against CSCs. Recently, immunotherapy has made rapid advances in cancer treatment, and its potential against CSCs is also an interesting area of research. Meanwhile, immunotherapy strategies are novel therapeutic modalities with promising results in targeting CSCs. In this review, we summarize the targeting of CSCs by various immunotherapy strategies such as monoclonal antibodies(mAb), tumor vaccines, immune checkpoint inhibitors, and chimeric antigen receptor-T cells(CAR-T) in pre-clinical and clinical studies. This review provides new insights into the application of these immunotherapeutic approaches to potential anti-tumor therapies in the future.

Sniping Cancer Stem Cells with Nanomaterials

Cancer stem cells (CSCs) drive tumor initiation, progression, and therapeutic resistance due to their self-renewal and differentiation capabilities. Despite encouraging progress in cancer treatment, conventional approaches often fail to eliminate CSCs, necessitating the development of precise targeted strategies. Recent advances in materials science and nanotechnology have enabled promising CSC-targeted approaches, harnessing the power of tailoring nanomaterials in diverse therapeutic applications. This review provides an update on the current landscape of nanobased precision targeting approaches against CSCs. We elucidate the nuanced application of organic, inorganic, and bioinspired nanomaterials across a spectrum of therapeutic paradigms, encompassing targeted therapy, immunotherapy, and multimodal synergistic therapies. By examining the accomplishments and challenges in this potential field, we aim to inform future efforts to advance nanomaterial-based therapies toward more effective "sniping" of CSCs and tumor clearance.

Histone lactylation-derived LINC01127 promotes the self-renewal of glioblastoma stem cells via the cis-regulating the MAP4K4 to activate JNK pathway

Gliomas are the most prevalent and aggressive brain tumors, exhibiting high proliferation, abnormal glycolysis, and poor prognosis. LncRNAs act as regulatory molecules and play crucial roles in the malignant behaviors of GBM cells, including cell self-renewal. However, the regulatory mechanisms involved are largely unknown. In this study, we performed bioinformatics analysis to explore NF-κB pathway-related lncRNAs. ECAR and qRT-PCR were used to measure the relationship between glycolytic activity and lncRNA expression. Assays such as RIP-PCR and ChIP-PCR were employed to reveal the regulatory mechanisms of the lncRNA. Neurosphere formation and limiting dilution assays were performed to evaluate the self-renewal capacity of GBM cells. In our study, we identified an NF-κB pathway-related lncRNA named LINC01127 in GBM, which was found to be associated with poor progression of GBM. Functionally, the NF-κB pathway promoted warburg effect, which, in turn, induced the lactylation of H3 histone and increased the expression of LINC01127. Consequently, this enhancement of LINC01127 expression led to the promotion of self-renewal in GBM cells. Furthermore, LINC01127 regulated MAP4K4 expression in cis by directly guiding POLR2A to the MAP4K4 promoter regions, thereby leading to JNK pathway activation, and ultimately modulating the self-renewal of GBM cells. Moreover, the activated JNK pathway promoted the phosphorylation of IκBα. Overall, targeting LINC01127-mediated axis impeded orthotopic tumor growth in GBM xenografts. Taken together these results revealed that warburg effect-induced histone lactylation drives NF-κB-related LINC01127 expression, thereby promoting the self-renewal of GBM cells through the MAP4K4/JNK/NF-κB axis, and providing substantial evidence that LINC01127 might provide a novel therapeutic strategy for GBM patients.

NF-κB signaling activation and roles in thyroid cancers: implication of MAP3K14/NIK

Among follicular-derived thyroid cancers (TC), those with aggressive behavior and resistance to current treatments display poor prognosis. NF-κB signaling pathways are involved in tumor progression of various cancers. Here, we finely characterize the NF-κB pathways and their involvement in TC. By using immunoblot and gel shift assays, we demonstrated that both classical and alternative NF-κB pathways are activated in ten TC-derived cell lines, leading to activated RelA/p50 and RelB/p50 NF-κB dimers. By analyzing the RNAseq data of the large papillary thyroid carcinoma (PTC) cohort from The Cancer Genome Atlas (TCGA) project, we identified a tumor progression-related NF-κB signature in BRAFV600E mutated-PTCs. That corroborated with the role of RelA and RelB in cell migration and invasion processes that we demonstrated specifically in BRAFV600E mutated-cell lines, together with their role in the control of expression of genes implicated in invasiveness (MMP1, PLAU, LCN2 and LGALS3). We also identified NF-κB-inducing kinase (NIK) as a novel actor of the constitutive activation of the NF-κB pathways in TC-derived cell lines. Finally, its implication in invasiveness and its overexpression in PTC samples make NIK a potential therapeutic target for advanced TC treatment.

ISG15 and ISGylation modulates cancer stem cell-like characteristics in promoting tumor growth of anaplastic thyroid carcinoma

BACKGROUND

Anaplastic thyroid carcinoma (ATC) was a rare and extremely malignant endocrine cancer with the distinct hallmark of high proportion of cancer stem cell-like characteristics. Therapies aiming to cancer stem-like cells (CSCs) were emerging as a new direction in cancer treatment, but targeting ATC CSCs remained challenging, mainly due to incomplete insights of the regulatory mechanism of CSCs. Here, we unveiled a novel role of ISG15 in the modulation of ATC CSCs.

METHODS

The expression of ubiquitin-like proteins were detected by bioinformatics and immunohistochemistry. The correlation between ISG15 expression and tumor stem cells and malignant progression of ATC was analyzed by single-cell RNA sequence from the Gene Expression Omnibus. Flow cytometry combined with immunofluorescence were used to verify the enrichment of ISG15 and ISGyaltion in cancer stem cells. The effect and mechanism of ISG15 and KPNA2 on cancer stem cell-like characteristics of ATC cells were determined by molecular biology experiments. Mass spectrometry combined with immunoprecipitation to screen the substrates of ISG15 and validate its ISGylation modification. Nude mice and zebrafish xenograft models were utilized to demonstrate that ISG15 regulates stem cell characteristics and promotes malignant progression of ATC.

RESULTS

We found that among several ubiquitin proteins, only ISG15 was aberrantly expressed in ATC and enriched in CSCs. Single-cell sequencing analysis revealed that abnormal expression of ISG15 were intensely associated with stemness and malignant cells in ATC. Inhibition of ISG15 expression dramatically attenuated clone and sphere formation of ATC cells, and facilitated its sensitivity to doxorubicin. Notably, overexpression of ISGylation, but not the non-ISGylation mutant, effectively reinforced cancer stem cell-like characteristics. Mechanistically, ISG15 mediated the ISGylation of KPNA2 and impeded its ubiquitination to promote stability, further maintaining cancer stem cell-like characteristics. Finally, depletion of ISG15 inhibited ATC growth and metastasis in xenografted mouse and zebrafish models.

CONCLUSION

Our studies not only provided new insights into potential intervention strategies targeting ATC CSCs, but also uncovered the novel biological functions and mechanisms of ISG15 and ISGylation for maintaining ATC cancer stem cell-like characteristics.

Suspension culture strategies to enrich colon cancer stem cells

How to efficiently obtain high-purity cancer stem cells (CSCs) has been the basis of CSC research, but the optimal conditions for serum-free suspension culture of CSCs are still unclear. The present study aimed to define the optimal culture medium composition and culture time for the enrichment of colon CSCs via suspension culture. Suspension cell cultures of colon cancer DLD-1 cells were prepared using serum-free medium (SFM) containing variable concentrations of epidermal growth factor (EGF) and basic fibroblast growth factor (bFGF) to produce spheroids. Culture times were set at 10, 20 and 30 days. A total of nine different concentrations of EGF and bFGF were added to SFM to generate nine experimental groups. The proportions of CD44⁺, CD133⁺, and CD44⁺CD133⁺ double-positive spheroid cells were detected via flow cytometry. mRNA expression of stemness-, epithelial-mesenchymal transition- and Wnt/β-catenin pathway-associated genes was determined via reverse transcription-quantitative PCR. Self-renewal ability was evaluated by a sphere-forming assay. Tumorigenesis was studied in vitro using a colony formation assay and in vivo via subcutaneous cell injection in nude mice. It was found that the highest expression proportions of CD133⁺ and CD44⁺ spheroid cells were observed in group (G)9 (20 ng/ml EGF + 20 ng/ml bFGF) at 30 days (F=123.554 and 99.528, respectively, P<0.001), CD133⁺CD44⁺ cells were also observed in G9 at 30 days (and at 10 days in G3 and 20 days in G6; F=57.897, P<0.001). G9 at 30 days also displayed the highest expression of Krüppel-like factor 4, leucine-rich repeat-containing G protein-coupled receptor 5, CD44, CD133, Vimentin and Wnt-3a (F=22.682, 25.401, 3.272, 7.852, 13.331 and 17.445, respectively, P<0.001) and the lowest expression of E-cadherin (F=10.851, P<0.001). G9 at 30 days produced the highest yield of cell spheroids, as determined by a sphere forming assay (F=19.147, P<0.001); colony formation assays also exhibited the greatest number of colonies derived from G9 spheroids at 30 days (F=60.767, P<0.01), which also generated the largest mean tumor volume in the subcutaneous tumorigenesis xenograft model (F=12.539, P<0.01). In conclusion, 20 ng/ml EGF + 20 ng/ml bFGF effectively enriched colon CSCs when added to suspension culture for 30 days, and conferred the highest efficiency compared with other combinations.

Dual Inhibition of BRAF-MAPK and STAT3 Signaling Pathways in Resveratrol-Suppressed Anaplastic Thyroid Cancer Cells with BRAF Mutations

Anaplastic thyroid cancer is an extremely lethal malignancy without reliable treatment. BRAFV600E point mutation is common in ATCs, which leads to MAPK signaling activation and is regarded as a therapeutic target. Resveratrol inhibits ATC cell growth, while its impact on BRAF-MAPK signaling remains unknown. This study aims to address this issue by elucidating the statuses of BRAF-MAPK and STAT3 signaling activities in resveratrol-treated THJ-11T, THJ-16T, and THJ-21T ATC cells and Nthyori 3-1 thyroid epithelial cells. RT-PCR and Sanger sequencing revealed MKRN1-BRAF fusion mutation in THJ-16T, BRAF V600E point mutation in THJ-21T, and wild-type BRAF genes in THJ-11T and Nthyori 3-1 cells. Western blotting and immunocytochemical staining showed elevated pBRAF, pMEK, and pERK levels in THJ-16T and THJ-21T, but not in THJ-11T or Nthyori 3-1 cells. Calcein/PI, EdU, and TUNEL assays showed that compared with docetaxel and doxorubicin and MAPK-targeting dabrafenib and trametinib, resveratrol exerted more powerful inhibitory effects on mutant BRAF-harboring THJ-16T and THJ-21T cells, accompanied by reduced levels of MAPK pathway-associated proteins and pSTAT3. Trametinib- and dabrafenib-enhanced STAT3 activation was efficiently suppressed by resveratrol. In conclusion, resveratrol acts as dual BRAF-MAPK and STAT3 signaling inhibitor and a promising agent against ATCs with BRAF mutation.

SYTL5 Promotes Papillary Thyroid Carcinoma Progression by Enhancing Activation of the NF-κB Signaling Pathway

The function and mechanism of SYTL5 in papillary thyroid carcinoma (PTC) are still unclear. In this research, we found that SYTL5 was significantly overexpressed in PTC tissues compared with normal thyroid tissues. SYTL5 downregulation significantly weakened the proliferative, migratory, and invasive abilities of PTC cells. In addition, upregulated SYTL5 could promote cancer progression by activating the NF-κB signaling pathway. RAC1b expression is positively associated with SYTL5, and overexpressed RAC1b abrogated the antitumor effect after SYTL5 inhibition. In conclusion, our findings identify the oncogenic role of SYTL5 in PTC by activation of the NF-κB signaling pathway, thus facilitating PTC development and progression.

NEDD9 links anaplastic thyroid cancer stemness to chromosomal instability through integrated centrosome asymmetry and DNA sensing regulation

Stemness and chromosomal instability (CIN) are two common contributors to intratumor heterogeneity and therapy relapse in advanced cancer, but their interplays are poorly defined. Here, in anaplastic thyroid cancer (ATC), we show that ALDH+ stem-like cancer cells possess increased CIN-tolerance owing to transcriptional upregulation of the scaffolding protein NEDD9. Thyroid patient tissues and transcriptomic data reveals NEDD9/ALDH1A3 to be co-expressed and co-upregulated in ATC. Compared to bulk ALDH- cells, ALDH+ cells were highly efficient at propagating CIN due to their intrinsic tolerance of both centrosome amplification and micronuclei. ALDH+ cells mitigated the fitness-impairing effects of centrosome amplification by partially inactivating supernumerary centrosomes. Meanwhile, ALDH+ cells also mitigated cell death caused by micronuclei-mediated type 1 interferon secretion by suppressing the expression of the DNA-sensor protein STING. Both mechanisms of CIN-tolerance were lost upon RNAi-mediated NEDD9 silencing. Both in vitro and in vivo, NEDD9-depletion attenuated stemness, CIN, cell/tumor growth, while enhancing paclitaxel effectiveness. Collectively, these findings reveal that ATC progression can involve an ALDH1A3/NEDD9-regulated program linking their stemness to CIN-tolerance that could be leveraged for ATC treatment.

Signaling Pathways and Targeted Therapies for Stem Cells in Prostate Cancer

Prostate cancer (PCa) is one of the most frequently occurring cancers among men, and the current statistics show that it is the second leading cause of cancer-related deaths among men. Over the years, research in PCa treatment and therapies has made many advances. Despite these efforts, the standardized therapies such as radiation, chemotherapy, hormonal therapy and surgery are not considered completely effective in treating advanced and metastatic PCa. In most situations, fast-dividing tumor cells are targeted, leaving behind relatively slowly dividing, chemoresistant cells known as cancer stem cells. Therefore, following the seemingly successful treatments, the lingering quiescent cancer stem cells are able to renew themselves, undergo differentiation into mature tumor cells, and sufficiently reinitiate the disease, leading to cancer relapse. Thus, prostate cancer stem cells (PCSCs) have been reported to play a vital role in controlling the dynamics of tumorigenesis, progression, and resistance to therapies in PCa. However, the complete knowledge on the mechanisms regulating the stemness of PCSCs is still unclear. Thus, studying the stemness of PCSCs will allow for the development of more effective cancer therapies due to the durable response, resulting in a reduction in recurrences of cancer. In this Review, we will specifically describe the molecular mechanisms responsible for regulating the stemness of PCSCs. Furthermore, current developments in stem cell-specific therapeutic approaches along with future prospects will also be discussed.

The endosomal pH regulator NHE9 is a driver of stemness in glioblastoma

A small population of self-renewing stem cells initiate tumors and maintain therapeutic resistance in glioblastoma (GBM). Given the limited treatment options and dismal prognosis for this disease, there is urgent need to identify drivers of stem cells that could be druggable targets. Previous work showed that the endosomal pH regulator NHE9 is upregulated in GBM and correlates with worse survival prognosis. Here, we probed for aberrant signaling pathways in patient-derived GBM cells and found that NHE9 increases cell surface expression and phosphorylation of multiple receptor tyrosine kinases (RTKs) by promoting their escape from lysosomal degradation. Downstream of NHE9-mediated receptor activation, oncogenic signaling pathways converged on the JAK2-STAT3 transduction axis to induce pluripotency genes Oct4 and Nanog and suppress markers of glial differentiation. We used both genetic and chemical approaches to query the role of endosomal pH in GBM phenotypes. Loss-of-function mutations in NHE9 that failed to alkalinize endosomal lumen did not increase self-renewal capacity of gliomaspheres in vitro. However, monensin, a chemical mimetic of Na+/H+ exchanger activity, and the H+ pump inhibitor bafilomycin bypassed NHE9 to directly alkalinize the endosomal lumen resulting in stabilization of RTKs and induction of Oct4 and Nanog. Using orthotopic models of primary GBM cells we found that NHE9 increased tumor initiation in vivo. We propose that NHE9 initiates inside-out signaling from the endosomal lumen, distinct from the established effects of cytosolic and extracellular pH on tumorigenesis. Endosomal pH may be an attractive therapeutic target that diminishes stemness in GBM, agnostic of specific receptor subtype.

NCOA3 is a critical oncogene in thyroid cancer via the modulation of major signaling pathways

PURPOSE

The Nuclear Receptor Coactivator (NCOA3, also known as SRC-3, AIB1, p/CIP, RAC3, ACTR, and TRAM1), acts as an oncogene in multiple tumors, but its biological function in thyroid cancer remains unclear. This study was designed to explore the role of NCOA3 in thyroid cancer.

METHODS

The study assessed NCOA3 expression in thyroid cancer and their matched non-cancerous thyroid tissues at mRNA and protein levels. Then we evaluated the effect of NCOA3 on malignant activities of thyroid cancer cells. To better understand the oncogenic role of NCOA3 in thyroid tumorigenesis, we tested the effect of NCOA3 on major proteins related to thyroid cancer.

RESULTS

Our data demonstrated that protein expression of NCOA3 was significantly upregulated in thyroid cancer tissues. NCOA3 knockdown inhibited cell proliferation and invasion, and induced cell cycle arrest and apoptosis in thyroid cancer. Conversely, ectopic expression of NCOA3 promoted cell proliferation and invasiveness in thyroid cancer. Mechanistically, NCOA3 could improve the survival and invasiveness of thyroid cancer cells through the modulation of the ErbB, AKT, ERK, and β-catenin pathways.

CONCLUSION

Collectively, these findings suggest that NCOA3 is critical in the initiation and development of thyroid cancer, and might be a possible marker for prognosis and therapy.

Long Non-Coding RNA: A Potential Strategy for the Diagnosis and Treatment of Colorectal Cancer

Colorectal cancer (CRC), being one of the most commonly diagnosed cancers worldwide, endangers human health. Because the pathological mechanism of CRC is not fully understood, there are many challenges in the prevention, diagnosis, and treatment of this disease. Long non-coding RNAs (lncRNAs) have recently drawn great attention for their potential roles in the different stages of CRC formation, invasion, and progression, including regulation of molecular signaling pathways, apoptosis, autophagy, angiogenesis, tumor metabolism, immunological responses, cell cycle, and epithelial-mesenchymal transition (EMT). This review aims to discuss the potential mechanisms of several oncogenic lncRNAs, as well as several suppressor lncRNAs, in CRC occurrence and development to aid in the discovery of new methods for CRC diagnosis, treatment, and prognosis assessment.

Targeting Phosphatases and Kinases: How to Checkmate Cancer

Metastatic disease represents the major cause of death in oncologic patients worldwide. Accumulating evidence have highlighted the relevance of a small population of cancer cells, named cancer stem cells (CSCs), in the resistance to therapies, as well as cancer recurrence and metastasis. Standard anti-cancer treatments are not always conclusively curative, posing an urgent need to discover new targets for an effective therapy. Kinases and phosphatases are implicated in many cellular processes, such as proliferation, differentiation and oncogenic transformation. These proteins are crucial regulators of intracellular signaling pathways mediating multiple cellular activities. Therefore, alterations in kinases and phosphatases functionality is a hallmark of cancer. Notwithstanding the role of kinases and phosphatases in cancer has been widely investigated, their aberrant activation in the compartment of CSCs is nowadays being explored as new potential Achille's heel to strike. Here, we provide a comprehensive overview of the major protein kinases and phosphatases pathways by which CSCs can evade normal physiological constraints on survival, growth, and invasion. Moreover, we discuss the potential of inhibitors of these proteins in counteracting CSCs expansion during cancer development and progression.

Insights into Intra-Tumoral Heterogeneity: Transcriptional Profiling of Chemoresistant MPM Cell Subpopulations Reveals Involvement of NFkB and DNA Repair Pathways and Contributes a Prognostic Signature

Chemoresistance is a hallmark of malignant pleural mesothelioma (MPM) management and the expression of ALDH1A3 is responsible for the survival and activity of MPM chemoresistant cell subpopulations (ALDH^bright cells). We enriched mesothelioma ALDH^bright cells to near homogeneity by FACS sorting and an Aldefluor assay and performed unbiased Affymetrix gene expression profiling. Viability and ELISA assays were used to rule out significant apoptosis in the sorted cell subpopulations and to assess target engagement by butein. Statistical analysis of the results, pathway enrichment and promoter enrichment were employed for the generation of the data. Q-RTPCR was used to validate a subset of the identified, modulated mRNAs In this work, we started from the observation that the mRNA levels of the ALDH1A3 isoform could prognostically stratify MPM patients. Thus, we purified MPM ALDH^bright cells from NCI-H2595 cells and interrogated their gene expression (GES) profile. We analyzed the GES of the purified cells at both a steady state and upon treatment with butein (a multifunctional tetrahydroxy-chalcone), which abates the ALDH^bright cell number, thereby exerting chemo-sensitizing effects in vitro and in vivo. We identified 924 genes modulated in a statistically significant manner as a function of ALDH status and of the response to the inhibitor. Pathway and promoter enrichment identified the molecular determinant of high ALDH status and how butein treatment altered the molecular portrait of those chemoresistant cell subpopulations. Further, we unraveled an eighteen-gene signature with high prognostic significance for MPM patients, and showed that most of the identified prognostic contributors escaped the analysis of unfractionated samples. This work proves that digging into the unexplored field of intra-tumor heterogeneity (ITH) by working at the cell subpopulation level may provide findings of prognostic relevance, in addition to mechanistic insights into tumor resistance to therapy.

The role of P62 in the development of human thyroid cancer and its possible mechanism

BACKGROUND

Thyroid cancer is the most common malignancy in human endocrine system. Increasing evidence has indicated that p62 plays a key role in tumorigenesis. The roles and underlying molecular mechanisms of P62 in thyroid cancer, however, remain to be elucidated.

METHODS

The expression levels of P62 in thyroid tumor tissues and thyroid cancer cells were detected by western blotting and qRT-PCR. Then, the effects of up-regulation or down-regulation of P62 on thyroid cancer cell proliferation, migration, invasion, cell cycle and apoptosis were measured by CCK-8 assay, transwell assay, flow cytometry and transwell assay, respectively. In terms of the mechanism, P62 could stimulate thyroid cancer progression by the activation of nuclear factor-kappa B (NF-κB) signaling pathway.

RESULTS

P62 was highly expressed in thyroid tumor tissues. Furthermore, high expression of p62 was observed in PTC cell lines, and especially in the K1 and TPC-1 cells. In vitro, the up-regulation of p62 promoted cell proliferation, migration, and invasion of thyroid cancer cells, whereas the knockdown of p62 resulted in the opposite effect. Knock-down of P62 increased the number of cells in the G0/G1 phase but reduced it in the S and G2/M phase. Moreover, we confirmed that overexpression of p62 inactivated NF-κB pathway with sequencing analysis and bioinformatics analysis.

CONCLUSION

This research work suggested that p62 could promote PTC cell proliferation, migration, and invasion via NF-κB signaling pathway. Furthermore, p62 is a potential biomarker which might be closely related to the tumorigenesis in PTC. Its potential role as a therapeutic target for PTC is worthy of further study.

Effects of Dihydrotanshinone I on Proliferation and Invasiveness of Paclitaxel-Resistant Anaplastic Thyroid Cancer Cells

ATC is a very rare, but extremely aggressive form of thyroid malignancy, responsible for the highest mortality rate registered for thyroid cancer. In patients without known genetic aberrations, the current treatment is still represented by palliative surgery and systemic mono- or combined chemotherapy, which is often not fully effective for the appearance of drug resistance. Comprehension of the mechanisms involved in the development of the resistance is therefore an urgent issue to suggest novel therapeutic approaches for this very aggressive malignancy. In this study, we created a model of anaplastic thyroid cancer (ATC) cells resistant to paclitaxel and investigated the characteristics of these cells by analyzing the profile of gene expression and comparing it with that of paclitaxel-sensitive original ATC cell lines. In addition, we evaluated the effects of Dihydrotanshinone I (DHT) on the viability and invasiveness of paclitaxel-resistant cells. ATC paclitaxel-resistant cells highlighted an overexpression of ABCB1 and a hyper-activation of the NF-κB compared to sensitive cells. DHT treatment resulted in a reduction of viability and clonogenic ability of resistant cells. Moreover, DHT induces a decrement of NF-κB activity in SW1736-PTX and 8505C-PTX cells. In conclusion, to the best of our knowledge, the results of the present study are the first to demonstrate the antitumor effects of DHT on ATC cells resistant to Paclitaxel in vitro.

Current Study of RhoA and Associated Signaling Pathways in Gastric Cancer

Gastric cancer (GC) is the fourth-most common cancer in the world, with an estimated 1.034 million new cases in 2015, and the third-highest cause of cancer deaths, estimated at 785,558, in 2014. Early diagnosis and treatment greatly affect the survival rate in patients with GC: the 5-year survival rate of early GC reaches 90%-95%, while the mortality rate significantly increases if GC develops to the late stage. Recently, studies for the role of RhoA in the diseases have become a hot topic, especially in the development of tumors. A study found that RhoA can regulate actin polymerization, cell adhesion, motor-myosin, cell transformation, and the ability to participate in the activities of cell movement, proliferation, migration, which are closely related to the invasion and metastasis of tumor cells. However, the specific role of RhoA in tumor cells remains to be studied. Therefore, our current study aimed to briefly review the role of RhoA in GC, especially for its associated signaling pathways involved in the GC progression.

Curcumin inhibits the viability, migration and invasion of papillary thyroid cancer cells by regulating the miR-301a-3p/STAT3 axis

Thyroid cancer is one of the most common malignant tumors, and the mortality rate associated with thyroid cancer has been increasing annually. Curcumin has been reported to exert an antitumor effect on papillary thyroid cancer (PTC), and the identification of additional mechanisms underlying the anticancer effect of curcumin on PTC requires further investigation. The present study aimed to explore the effects of curcumin on the viability, migration and invasion of PTC cells. TPC-1 cells were incubated with different concentrations of curcumin, and then, cell viability, migration and invasion, and wound healing were examined by CCK-8, Transwell and wound healing assays, respectively. Subsequently, microRNA (miR)-301a-3p mimics, miR-301a-3p inhibitors and signal transducer and activator of transcription (STAT)3 overexpression vector were transfected into TPC-1 cells, and cell viability, migration, and invasion were reassessed in these transfected cells. Matrix metallopeptidase (MMP)-2, MMP-9, epithelial-mesenchymal transition (EMT)-related markers, and Janus kinase (JAK)/STAT signaling pathway components were assessed by western blot analysis. Curcumin significantly inhibited cell viability, migration and invasion and downregulated MMP-2, MMP-9 and EMT marker expression. Additionally, curcumin decreased STAT3 expression by upregulating miR-301a-3p expression, and the inhibition of miR-301a-3p and the overexpression of STAT3 reversed the effects of curcumin on cell viability, migration and invasion, and MMP-2, MMP-9 and EMT marker expression in TPC-1 cells. Furthermore, curcumin suppressed the JAK/STAT signaling pathway through the miR-301a-3p/STAT3 axis. The data of the present study indicated that curcumin could inhibit the viability, migration and invasion of TPC-1 cells by regulating the miR-301a-3p/STAT3 axis. These findings may provide a possible strategy for the clinical treatment of PTC.

Signal transducer and activator of transcription 3 inhibition alleviates resistance to BRAF inhibition in anaplastic thyroid cancer

Anaplastic thyroid cancer (ATC) is a rare type of thyroid cancer (TC) with no effective therapeutic strategy. Although surgery, chemotherapy and radiation are all available for ATC treatment, the median survival for ATC patients is less than 6 months. In this study, we aimed to study on resistant mechanisms to B-Raf proto-oncogene serine/threonine kinase (BRAF) inhibitor and identify effective combinational therapy for ATC patients. TC cells were treated with Vemurafenib and cell apoptosis and viability were analyzed by flow cytometry and MTT assay. Monolayer and sphere cells were isolated from ATC cells to detect the mRNA level of stem cell markers and differentiation markers by RT-PCR. Phosphor-STAT3 level in sphere and monolayer cells was tested by Western blotting. The xenotransplantation animal model has established to analyze the anti-tumor effect of Vemurafenib and Stattic combinational therapy. Undifferentiated TC cells were resistant to Vemurafenib treatment. Sphere cells isolated from ATC showed no significant change in cell viability and apoptosis upon Vemurafenib treatment, and expressed a high level of stem cell marker and phosphor-STAT3. STAT3 inhibition enhanced the tumorigenic capacity and increased Vemurafenib sensitivity in ATC cell lines. Stattic significantly enhanced anti-tumor effect of Vemurafenib in mouse model. Our findings demonstrate that the combinational therapy of Vemurafenib and Stattic is an effective therapeutic treatment for ATC patients.

Diallyl trisulfide inhibited tobacco smoke-mediated bladder EMT and cancer stem cell marker expression via the NF-κB pathway in vivo

OBJECTIVE

This study examined the effect of the NF-κB pathway on tobacco smoke-elicited bladder epithelial-mesenchymal transition (EMT) and cancer stem cell (CSC) marker expression in vivo. The effect of diallyl trisulfide (DATS) treatment was also examined.

METHODS

BALB/c mice were exposed to tobacco smoke and treated with an NF-κB inhibitor and DATS. Western blotting, quantitative real-time PCR, and immunohistochemical staining were used to detect the changes of relevant indices.

RESULTS

Phosphorylated inhibitor of kappa-B kinase alpha/beta expression and p65 and p50 nuclear transcription were increased by tobacco smoke exposure, whereas inhibitor of kappa-B expression was decreased. In addition, tobacco smoke reduced the expression of epithelial markers but increased that of mesenchymal and CSC markers. Our study further demonstrated that tobacco smoke-mediated EMT and CSC marker expression were attenuated by inhibition of the NF-κB pathway. Moreover, DATS reversed tobacco smoke-induced NF-κB pathway activation, EMT, and the acquisition of CSC properties in bladder tissues.

CONCLUSIONS

These data suggested that the NF-κB pathway regulated tobacco smoke-induced bladder EMT, CSC marker expression, and the protective effects of DATS.

STAT3 signaling statuses determine the fate of resveratrol-treated anaplastic thyroid cancer cells

BACKGROUNDS

Anaplastic thyroid cancer/ATC is highly lethal malignancy without reliable chemotherapeutic drug. Resveratrol possesses anti-ATC activities but encounters resistance in some cases due to certain unknown reason(s).

OBJECTIVE

Because signal transducer and activator of transcription/STAT3 signaling is critical for ATC cell survival and the main molecular target of resveratrol, its roles in determining the fates of resveratrol-treated ATC cells were investigated here.

METHODS

Human THJ-11T, THJ-16 and THJ-21T ATC cell lines were treated by 100 μM resveratrol and their growth, statuses of STAT3 signaling and STAT3-related gene expression were examined. The relevance of STAT3 activation with resveratrol resistance was elucidated using STAT selective inhibitor AG490. Leukemia inhibitory factor/LIF expression and phosphorylated-STAT3/p-STAT3 nuclear translocation in ATC tissues were immunohistochemically analyzed.

RESULTS

Resveratrol inhibited proliferation, p-STAT3 nuclear translocation as well as LIF and STAT3 expression of THJ-16T and THJ-21T but not THJ-21T cells which showed LIF upregulation and more frequent p-STAT3 nuclear translocation. AG490 significantly prevent p-STAT3 nuclear translocation, and reversed the resveratrol tolerance of THJ-11T cells. Immonohistochemical staining revealed 14.3% (4/28) of LIF and 3.6% (1/28) of p-STAT3 detection in noncancerous ATC-surrounding tissues, which increased to 89.5% (17/19) and 52.6% (10/19) respectively among ATC specimens. The correlative analysis indicated the relevance of LIF expression and STAT3 activation (r= 0.825; P< 0.01).

CONCLUSIONS

The status of STAT3 activation and LIF expression are closely correlated with the therapeutic effect of resveratrol on ATCs. Frequent LIF upregulation and STAT3 activation are the unfavorable factors of ATCs and the potential targets of anti-ATC therapy.

Long noncoding RNA LINC01578 drives colon cancer metastasis through a positive feedback loop with the NF-κB/YY1 axis

Metastasis accounts for poor prognosis of cancers and related deaths. Accumulating evidence has shown that long noncoding RNAs (lncRNAs) play critical roles in several types of cancer. However, which lncRNAs contribute to metastasis of colon cancer is still largely unknown. In this study, we found that lncRNA LINC01578 was correlated with metastasis and poor prognosis of colon cancer. LINC01578 was upregulated in colon cancer, associated with metastasis, advanced clinical stages, poor overall survival, disease-specific survival, and disease-free survival. Gain-of-function and loss-of-function assays revealed that LINC01578 enhanced colon cancer cell viability and mobility in vitro and colon cancer liver metastasis in vivo. Mechanistically, nuclear factor kappa B (NF-κB) and Yin Yang 1 (YY1) directly bound to the LINC01578 promoter, enhanced its activity, and activated LINC01578 expression. LINC01578 was shown to be a chromatin-bound lncRNA, which directly bound NFKBIB promoter. Furthermore, LINC01578 interacted with and recruited EZH2 to NFKBIB promoter and further repressed NFKBIB expression, thereby activating NF-κB signaling. Through activation of NF-κB, LINC01578 further upregulated YY1 expression. Through activation of the NF-κB/YY1 axis, LINC01578 in turn enhanced its own promoter activity, suggesting that LINC01578 and NF-κB/YY1 formed a positive feedback loop. Blocking NF-κB signaling abolished the oncogenic roles of LINC01578 in colon cancer. Furthermore, the expression levels of LINC01578, NFKBIB, and YY1 were correlated in clinical tissues. Collectively, this study demonstrated that LINC01578 promoted colon cancer metastasis via forming a positive feedback loop with NF-κB/YY1 and suggested that LINC01578 represents a potential prognostic biomarker and therapeutic target for colon cancer metastasis.

Thyroid Cancer and Circadian Clock Disruption

Simple Summary

In this manuscript we review the recent literature supporting a biological link between circadian clock disruption and thyroid cancer development and progression. After a brief description of the involvement of the circadian clock machinery in the cell cycle, stemness and cancer, we discuss the scientific evidence supporting the contribution of circadian clockwork dysfunction in thyroid tumorigenesis and the possible molecular mechanisms underlying this relationship. We also point out the potential clinical implications of this link highlighting its impact on thyroid cancer prevention, diagnosis and therapy.

Abstract

Thyroid cancer (TC) represents the most common malignancy of the endocrine system, with an increased incidence across continents attributable to both improvement of diagnostic procedures and environmental factors. Among the modifiable risk factors, insulin resistance might influence the development of TC. A relationship between circadian clock machinery disfunction and TC has recently been proposed. The circadian clock machinery comprises a set of rhythmically expressed genes responsible for circadian rhythms. Perturbation of this system contributes to the development of pathological states such as cancer. Several clock genes have been found deregulated upon thyroid nodule malignant transformation. The molecular mechanisms linking circadian clock disruption and TC are still unknown but could include insulin resistance. Circadian misalignment occurring during shift work, jet lag, high fat food intake, is associated with increased insulin resistance. This metabolic alteration, in turn, is associated with a well-known risk factor for TC i.e., hyperthyrotropinemia, which could also be induced by sleep disturbances. In this review, we describe the mechanisms controlling the circadian clock function and its involvement in the cell cycle, stemness and cancer. Moreover, we discuss the evidence supporting the link between circadian clockwork disruption and TC development/progression, highlighting its potential implications for TC prevention, diagnosis and therapy.

Identification of Hub Genes in Anaplastic Thyroid Carcinoma: Evidence From Bioinformatics Analysis

Anaplastic thyroid carcinoma (ATC) is a rare type of thyroid cancer that results in fatal clinical outcomes; the pathogenesis of this life-threatening disease has yet to be fully elucidated. This study aims to identify the hub genes of ATC that may play key roles in ATC development and could serve as prognostic biomarkers or therapeutic targets. Two microarray datasets (GSE33630 and GSE53072) were obtained from the Gene Expression Omnibus database; these sets included 16 ATC and 49 normal thyroid samples. Differential expression analyses were performed for each dataset, and 420 genes were screened as common differentially expressed genes using the robust rank aggregation method. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses were conducted to explore the potential bio-functions of these differentially expressed genes (DEGs). The terms and enriched pathways were primarily associated with cell cycle, cell adhesion, and cancer-related signaling pathways. Furthermore, a protein-protein interaction network of DEG expression products was constructed using Cytoscape. Based on the whole network, we identified 7 hub genes that included CDK1, TOP2A, CDC20, KIF11, CCNA2, NUSAP1, and KIF2C. The expression levels of these hub genes were validated using quantitative polymerase chain reaction analyses of clinical specimens. In conclusion, the present study identified several key genes that are involved in ATC development and provides novel insights into the understanding of the molecular mechanisms of ATC development.

The Possible Role of Cancer Stem Cells in the Resistance to Kinase Inhibitors of Advanced Thyroid Cancer

Target therapy with various kinase inhibitors (KIs) has been extended to patients with advanced thyroid cancer, but only a subset of these compounds has displayed efficacy in clinical use. However, after an initial response to KIs, dramatic disease progression occurs in most cases. With the discovery of cancer stem cells (CSCs), it is possible to postulate that thyroid cancer resistance to KI therapies, both intrinsic and acquired, may be sustained by this cell subtype. Indeed, CSCs have been considered as the main drivers of metastatic activity and therapeutic resistance, because of their ability to generate heterogeneous secondary cell populations and survive treatment by remaining in a quiescent state. Hence, despite the impressive progress in understanding of the molecular basis of thyroid tumorigenesis, drug resistance is still the major challenge in advanced thyroid cancer management. In this view, definition of the role of CSCs in thyroid cancer resistance may be crucial to identifying new therapeutic targets and preventing resistance to anti-cancer treatments and tumor relapse. The aim of this review is to elucidate the possible role of CSCs in the development of resistance of advanced thyroid cancer to current anti-cancer therapies and their potential implications in the management of these patients.

Glycochenodeoxycholic acid induces stemness and chemoresistance via the STAT3 signaling pathway in hepatocellular carcinoma cells

The poor prognosis of hepatocellular carcinoma (HCC) is primarily attributed to its high frequency of recurrence and resistance to chemotherapy. Epithelial-to-mesenchymal transition (EMT) and the acquisition of cancer stem cells (CSCs) are the fundamental drivers of chemoresistance in HCC. Glycochenodeoxycholic acid (GCDC), a component of bile acid (BA), has been reported to induce necrosis in primary human hepatocytes. In the present work, we investigated the function of GCDC in HCC chemoresistance. We found that GCDC promoted chemoresistance in HCC cells by down-regulating and up-regulating the expression of apoptotic and anti-apoptotic genes, respectively. Furthermore, GCDC induced the EMT phenotype and stemness in HCC cells and activated the STAT3 signaling pathway. These findings reveal that GCDC promotes chemoresistance in HCC by inducing stemness via the STAT3 pathway and could be a potential target in HCC chemotherapy.

Anticancer Activity of Novel NF-kappa B Inhibitor DHMEQ by Intraperitoneal Administration

There have been great advances in the therapy of cancer and leukemia. However, there are still many neoplastic diseases that are difficult to treat. For example, it is often difficult to find effective therapies for aggressive cancer and leukemia. An NF-κB inhibitor named dehydroxymethylepoxyquinomicin (DHMEQ) was discovered in 2000. This compound was designed based on the structure of epoxyquinomicin isolated from a microorganism. It was shown to be a specific inhibitor that directly binds to and inactivates NF-κB components. Until now, DHMEQ has been used by many scientists in the world to suppress animal models of cancer and inflammation. Especially, it was shown to suppress difficult cancer models, such as hormone-insensitive breast cancer and prostate cancer, cholangiocarcinoma, and multiple myeloma. No toxicity has been reported so far. DHMEQ was administered via the intraperitoneal (IP) route in most of the animal experiments because of its simplicity. In the course of developmental studies, it was found that IP administration never increased the blood concentration of DHMEQ because of the instability of DHMEQ in the blood. It is suggested that inflammatory cells in the peritoneal cavity would be important for cancer progression, and that IP administration, itself, is important for the effectiveness and safety of DHMEQ. In the present review, we describe mechanism of action, its in vivo anticancer activity, and future clinical use of DHMEQ IP therapy.

Synergy of GSK-J4 With Doxorubicin in KRAS-Mutant Anaplastic Thyroid Cancer

Background

Anaplastic thyroid cancer is the most aggressive thyroid cancer and has a poor prognosis. At present, there is no effective treatment for it.

Methods

Here, we used different concentrations of GSK-J4 or a combination of GSK-J4 and doxorubicin to treat human Cal-62, 8505C, and 8305C anaplastic thyroid cancer (ATC) cell lines. The in vitro experiments were performed using cell viability assays, cell cycle assays, annexin-V/PI binding assays, Transwell migration assays, and wound-healing assays. Tumor xenograft models were used to observe effects in vivo.

Results

The half maximal inhibitory concentration (IC50) of GSK-J4 in Cal-62 cells was 1.502 μM, and as the dose of GSK-J4 increased, more ATC cells were blocked in the G2-M and S stage. The combination of GSK-J4 and doxorubicin significantly increased the inhibitory effect on proliferation, especially in KRAS-mutant ATC cells in vivo (inhibition rate 38.0%) and in vitro (suppresses rate Fa value 0.624, CI value 0.673). The invasion and migration abilities of the KRAS-mutant cell line were inhibited at a low concentration (p < 0.05).

Conclusions

The combination of GSK-J4 with doxorubicin in KRAS-mutant ATC achieved tumor-suppressive effects at a low dose. The synergy of the combination of GSK-J4 and doxorubicin may make it an effective chemotherapy regimen for KRAS-mutant ATC.

Sanguinarine Induces Apoptosis in Papillary Thyroid Cancer Cells via Generation of Reactive Oxygen Species

Sanguinarine (SNG), a natural compound with an array of pharmacological activities, has promising therapeutic potential against a number of pathological conditions, including malignancies. In the present study, we have investigated the antiproliferative potential of SNG against two well-characterized papillary thyroid cancer (PTC) cell lines, BCPAP and TPC-1. SNG significantly inhibited cell proliferation of PTC cells in a dose and time-dependent manner. Western blot analysis revealed that SNG markedly attenuated deregulated expression of p-STAT3, without affecting total STAT3, and inhibited growth of PTC via activation of apoptotic and autophagy signaling cascade, as SNG treatment of PTC cells led to the activation of caspase-3 and caspase-8; cleavage of PARP and activation of autophagy markers. Further, SNG-mediated anticancer effects in PTC cells involved the generation of reactive oxygen species (ROS) as N-acetyl cysteine (NAC), an inhibitor of ROS, prevented SNG-mediated antiproliferative, apoptosis and autophagy inducing action. Interestingly, SNG also sensitized PTC cells to chemotherapeutic drug cisplatin, which was inhibited by NAC. Finally, SNG suppressed the growth of PTC thyrospheres and downregulated stemness markers ALDH2 and SOX2. Altogether, the findings of the current study suggest that SNG has anticancer potential against PTC cells as well its derived cancer stem-like cells, most likely via inactivation of STAT3 and its associated signaling molecules.

CCL21/CCR7 interaction promotes EMT and enhances the stemness of OSCC via a JAK2/STAT3 signaling pathway

Chemokines and their receptors show a strong relationship with poor clinical outcomes in various cancers. However, their underlying mechanisms remain to be fully elucidated. In our research, we found C-C chemokine receptor 7 (CCR7) and its ligand chemokine ligand 21 (CCL21) were abnormally abundant in oral squamous cell carcinoma (OSCC) tissues, and CCR7 expression was correlated with poor prognosis of OSCC. After exogenous CCL21 stimulation, epithelial-mesenchymal transition (EMT) was promoted in OSCC cells, and cancer stem cell-related markers CD133, CD44, BMI1, ALDH1A1, and OCT4 increased. The migration, invasion, tumorsphere formation, and colony formation abilities of OSCC cells were enhanced, indicating that the stemness of OSCC cells was also improved. The knockdown and overexpression of CCR7 efficiently affected the CCL21-induced EMT and stemness of OSCC cells. When treated with CCL21, the phospho-JAK2 and phospho-STAT3 markedly increased. The inhibitor of the Janus kinase 2/signal transducer and activator of transcription 3 (JAK2/STAT3) significantly suppressed CCL21-induced EMT and stemness of OSCC cells. In conclusion, CCL21/CCR7 axis regulated EMT progress and promoted the stemness of OSCC by activating the JAK2/STAT3 signaling pathway. CCL21/CCR7 might be an effective target for OSCC prevention and treatment.

Limonin enhances the radiosensitivity of nasopharyngeal carcinoma cells via attenuating Stat3-induced cell stemness

The inhibitory effects of limonin have been disclosed in various tumors, however, its roles in nasopharyngeal carcinoma (NPC) progression are never been revealed. In the current work, we collected NPC cells with a higher stemness compared with bulk cells through isolating the side population (SP) cells. It was found that limonin exhibited a stronger inhibitory effect on SP cells than that in bulk cells, which was evident by a lower IC50 value. Additionally, limonin attenuated the stemness and migration ability of SP cells with the higher stemness, characterized as decreasing the spheroid formation ability, expression of stemness markers and migration ability. Moreover, the proportion of SP cells in G0 phase was remarkably higher than that in bulk cells. Notably, upon limonin treatment, the proportion of SP cells in G0 was decreased and S/G2/M increased. Furthermore, limonin enhanced the radiosensitivity of NPC cells. The mechanistic studies based on RNA-sequencing analysis revealed that limonin inhibited the gene transcription driven by Stat3 (signal transducer and activator of transcription 3) and an activator of Stat3 (Colivelin or IL-6) rescued the inhibitory effects of limonin. Therefore, these results demonstrate that limonin could reduce the stemness of NPC cells and thus the radiosensitivity through suppressing Stat3 transcriptional activity.

A Systematic Review of Phase II Targeted Therapy Clinical Trials in Anaplastic Thyroid Cancer

Anaplastic thyroid carcinoma (ATC) is a rare, but devastating disease. Despite multimodal approaches combining surgery, chemotherapy and radiation therapy, ATC is associated with a dire prognosis, with a median overall survival of only three to ten months. Novel treatments are thus urgently needed. Recent efforts towards the characterization of the molecular landscape of ATC have led to the identification of pro-oncogenic targetable alterations, lending promise for novel targeted therapeutic approaches. This systematic review summarizes the results of phase II clinical trials of targeted therapy in ATC, providing an overview of efficacy and safety profiles. The majority of trials to date have consisted of small single-arm studies and have presented modest results. However, only a minority of trials have selected or stratified patients by molecular alterations. In the setting of BRAF V600E mutated ATC, dabrafenib/trametinib combination therapy and vemurafenib monotherapy have both demonstrated efficacy. Everolimus has furthermore shown promising results in patients with PI3K/mTOR/AKT pathway alterations. These studies underscore the importance of molecular profiling of tumors for appropriate patient selection and determination of genomic correlates of response. Clinical trials are underway testing additional targeted therapies as monotherapy, or as a part of multimodal treatment, and in combination with immunotherapy.